Hey Ben!
I have experienced the same issue and actually, I was just able to solve it...
My situation: Enpass Safari Extension Connection Error
I had a 2015 MacBook Pro running with macOS High Sierra. Enpass used to work fine with all browsers (Safari, Firefox, Chrome)
A couple of weeks ago I switched to a 2017 MacBook Pro via Migration Assistant. On my new MBP, Enpass still worked with Firefox and Chrome, but did not work with Safari!
Always displayed this dumb connection error...
Now here's what I did:
Uninstall and re-install Enpass for macOS (tried both the App-Store and the Enpass-Website versions)
Uninstall and re-install Enpass Safari Extension (tried both the Safari Extensions Gallery and the Enpass Website versions)
Install Enpass for macOS and Enpass Safari Extension DEBUG versions sent to me from Enpass support
And all of this didn't change a thing!
Here's what solved my issue:
After reinstalling Enpass and the respective safari extension about a million times, I decided to re-install macOS without erasing my data.
A reinstallation of macOS is the only way to re-install Safari.
How I did this:
Make a Time Machine backup to an external HDD or NAS.
Go to Mac App Store, search for High Sierra and download it (around 5 GB)
When the download is finished, the High Sierra Installer pops up
Simply re-install macOS this way (this does not affect your data!)
-> and then be happy things are working well again!
And - voilà - this solved the problem for me.
Now everything is working well!
Good luck,
Oliver

Hey guys!
I have experienced the same issue and actually, I just solved it by myself after the Enpass support turned out to be not exactly super helpful.
My situation: Enpass Safari Extension Connection Error
I had a 2015 MacBook Pro running with macOS High Sierra. Enpass used to work fine with all browsers (Safari, Firefox, Chrome)
A couple of weeks ago I switched to a 2017 MacBook Pro via Migration Assistant. On my new MBP, Enpass still worked with Firefox and Chrome, but did not work with Safari!
Always displayed this dumb connection error...
Now here's what I did:
Uninstall and re-install Enpass for macOS (tried both the App-Store and the Enpass-Website versions)
Uninstall and re-install Enpass Safari Extension (tried both the Safari Extensions Gallery and the Enpass Website versions)
Install Enpass for macOS and Enpass Safari Extension DEBUG versions sent to me from Enpass support
And all of this didn't change a thing!
Here's what solved my issue:
After reinstalling Enpass and the respective safari extension about a million times, I decided to re-install macOS without erasing my data.
A reinstallation of macOS is the only way to re-install Safari.
How I did this:
Make a Time Machine backup to an external HDD or NAS.
Go to Mac App Store, search for High Sierra and download it (around 5 GB)
When the download is finished, the High Sierra Installer pops up
Simply re-install macOS this way (this does not affect your data!)
-> and then be happy things are working well again!
And - voilà - this solved the problem for me.
Now everything is working well!
Good luck,
Oliver

Hey Ugomiller,
Enpass Browser extensions only work when the main application is active in the background.
Should you have a problem with the Enpass Safari Extension, I recommend first activating browser extensions (as you did according to your screenshot).
I had the following situation:
Browser extension worked fine in Firefox and Chrome. But not with Safari: it always displayed a connection error.
After reinstalling Enpass and the respective safari extension about a million times, I decided to re-install macOS without erasing my data.
A reinstallation of macOS is the only way to re-install Safari.
How I did this:
Make a Time Machine backup to an external HDD or NAS.
Go to Mac App Store, search for High Sierra and download it (around 5 GB)
When the download is finished, the High Sierra Installer pops up
Simply re-install macOS this way
And - voilà - this solved the problem for me.
Now everything is working fine!
Avec mes meilleures salutations,
Oli